Quote Originally Posted by DEvianT
I use x133 speed CF, SDHC and SD cards of various makes in my 1D MK2 and they are plenty fast enough. Now if they are fast enough for 8.5 fps then they are fast enough for anything.
The size of the buffer in your camera is more important than the card speed, unless you're holding down the button for a long, long time. The card speed only really kicks in after the buffer is full. I can't remember what it is for the 1D Mark II. But I think it's something like 20 frames before the camera actually starts saving directly to the card. At that point, it's the memory card speed that's the bottleneck. Before that, you aren't even touching it. Again, I think, for most of us, fast cards make the most difference when you're transferring files or formatting the cards. It matters most to me when I'm at an event trying to dump multiple cards to my laptop during a break.